You can also set the field to be hidden with the "Hidden" attribute, but if you want to change this through code later (to unhide the field) you'll need to set "CanToggleHidden='TRUE'" too. See this for more details.

You can show/hide fields in a SharePoint Form by setting the
conditional formattings with SharePoint Designer. Just open the
webform (e.g. NewForm.aspx) and switch to advanced mode. Then choose
the field you want to hide for specific user group and create a new
condition criteria... click advanced and paste "ddwrt:IfHasRights(16)"
(without quotes) in the field "Edit the XPath Expression".

1.) Not created in code 2.) editing the form in Designer doesn't allow editing the web part that actually displays the form. Editing is only possible for other parts.
–
Robert KoritnikJan 10 '11 at 13:49

View Rob's answer for doing it with SPDesigner.
–
James LoveJan 10 '11 at 14:18

You can do this with SharePoint Designer. You need to create a new site page, then use the insert new or edit form buttons at the top to insert a Data View Web Part. Using this method you'll see a button on the ribbon that allows you to add/remove particular columns on the form.

A second approach is to use the default forms but use jQuery to hide the fields. The names are system generated so it will take a little digging.

If you want to use JavaScript to hide the fields, I would suggest taking a look at my library SPUtility.js: sputility.codeplex.com. I think it may work in SharePoint 2010 or at least give you an idea.
–
Kit MenkeJan 10 '11 at 14:22

Kit-Your project looks great. That's a nice idea, and timely. Is the code based on the field labels? I'll be keeping an eye on it!
–
Rob WilsonJan 10 '11 at 14:44

Thanks Rob. :) The code is based on the field labels and then creates little JavaScript "classes" based on the field type.
–
Kit MenkeJan 10 '11 at 16:50

I have used a tool called MOSS Show/Hide Fields (http://spiralout.codeplex.com/releases/view/22305). It runs on the client and lets you hide fields from moss forms (new,edit,display,view). It was built for SharePoint 2007, but I just tried it with SharePoint 2010 and it worked in my simple test.